1. Field of the Invention
This invention pertains to suspension systems for metallurgical articles (sideboards or hot tops) used at the top of an ingot mold to control solidification of the molten metal in the ingot mold.
In its broadest aspects, the Invention encompasses sideboards, the so-called monolithic hot tops and riser sleeves which are supported in a mold which receives molten metal.
In particular, the invention will be described in relation to sideboards used in molds which are commonly found in the steel mill. Sideboards are generally flat panels placed in the top of the ingot mold and can show insulating refractory or exothermic properties. The sideboards can be used in pairs or in fours to form a completely enclosed reservoir at the top of the ingot mold.
2. Description of the Prior Art
A conventional monolithic hot top and one suspension system therefor is illustrated in U.S. Pat. No. 1,794,840.
As an alternative to the monolithic hot top over the years, there have been various types of hot tops employing flat pieces (boards) of refractory or exothermic material which are assembled inside of the ingot mold. Illustrative of this type of composite hot top are the devices shown in U.S. Pat. Nos. 1,137,264; 1,501,655; 2,546,270; 3,165,798; and 3,202,395.
Another type of heat control product, and one that is used extensively with the so-called slab type ingot (one which has an elongated rectangular cross-section), is the sideboard illustrated in U.S. Pat. Nos. 3,103,045 and 3,144,698. The sideboards can be used in groups of four to achieve a hot top or closed reservoir as illustrated in U.S. Pat. No. 3,421,731.
When using a sideboard, the board must be supported against the wall of the ingot mold. The board must be held tightly to the ingot mold so that no metal flows between the board and the mold wall to chill against the mold wall thus depleating the reservoir of molten metal which feeds the balance of the ingot as it solidifies. The object of the sideboard is to control the temperature of the molten metal at the top of the ingot mold so that it solidifies less rapidly than the rest of the ingot mold and feeds additional metal to the major portion of the ingot mold as it solidifies.
All of the foregoing patents drawn to metallurgical sideboards and hot tops, illustrate various ways of fastening the board or the top to the ingot mold. Most commonly used are the clip type fasteners which are illustrated by U.S. Pat. Nos. 3,144,698 and 3,506,236.
Another type of hanger is the support hanger illustrated in U.S. Pat. Nos. 3,165,798 and 3,202,395. The hanger type, is as the name implies, a hanger which is supported by the top surface of the ingot mold. The hanger itself is either fastened to the hot top panels (U.S. Pat. No. 3,202,395) or communicates with an aperture in the hot top panels (U.S. Pat. No. 3,165,798).